According to court documents, Sadikovic contacted a person involved in one of her CPS cases and asked where she could purchase oxycodone or heroin.

The client reportedly exchanged text messages with Sadikovic under the direction of a Phoenix police detective and arranged to meet the caseworker later that evening for a drug deal.

Sadikovic allegedly arrived at the arranged location in a government-issued vehicle and purchased imitation heroin.

Sadikovic was arrested and later told detectives she was investigating her clients, police said.

Division of Child Safety and Family Services spokeswoman Jennifer Bowser-Richards said Sadikovic was fired Friday.

She was hired by CPS on Jan. 22, 2013 and held the position of CPS Specialist II, Bowser-Richards said. She reportedly had no supervisory responsibilities.

Bowser-Richards said CPS is conducting an internal investigation, which will include a review of all of Sadikovic's past and current cases. CPS' internal affairs division is also cooperating with the police investigation.

"Such actions are illegal, a violation of our mission and violation of the public trust, and will not be tolerated," CPS Director Charles Flanagan said in a statement Friday.

Sadikovic's attorney says the caseworker has no criminal record and calls the arrest an isolated situation.

Sadikovic has been released from jail without bond after being charged with attempted possession of a narcotic drug, a class five felony.

She lives in Phoenix with her husband and son, according to court documents.